There was a great comparison replay between one of the Audis and the 7 Toyota into Stowe, the Audi was hitting the bumps quite badly too, but not as badly as the Toyota, the 7 car was porpoising like crazy.
The Audi just looked supreme in the corners, the drivers didn't have to be so aggressive on turn in unlike the Toyota's who had to really yank the front into both Copse and Stowe. The Rebellion cars were just as stiff at the front (but very soft in roll on the rear) as the Toyota ones, even lifting the inside wheels in the fast corners.